1. Field
One embodiment of the invention relates to various types of recyclable surface coverings. For example, the recyclable surface coverings include granulated rubber bottom (base) layers in combination with surface layers bonded to the granulated bottom layers. Another aspect of the invention relates to a system, such as a manufacturing line, that produces the above-noted recyclable surface covering. Another aspect of the invention relates to a process for manufacturing the above-noted recyclable surface covering. In one specific exemplary embodiment, a vinyl surface material is bonded to a recycled rubber cushioned bottom (base) layer (a.k.a. underlayment). This type of laminate has a number of positive characteristics such as flame retardation, smoke suppression, noise reduction, force reduction, and the ability to stay in place upon installation without the use of adhesives.
2. Description of the Related Art
Recyclable floor coverings include carpet, matting, wood, and tile. Carpet and matting, for example, rubber matting, typically require substantial amounts of solvents and/or adhesives during production or installation. Conventional solvents and adhesives produce emissions, which can be harmful to the environment.
Additionally, disposal of conventional carpets and matting poses difficulties inasmuch as these materials can be difficult to recycle. For example, conventional carpets and mattings are often formed of dissimilar materials, and therefore, conventional recycling techniques, which may include liquidation of the materials to be recycled, are relatively ineffective.
For example, one type of floor covering provides a flocked layer of nylon fibers electrostatically flocked onto a polyvinylchloride (PVC) backing. In production of this material, a glass fiber layer is added between a PVC backing and a flocking to provide dimensional stability. The flocked floor covering is screen printed to provide a wide range of patterns and colors. However, PVC is generally not considered to be easily recyclable. Furthermore, heating PVC, for example, in a liquidation process, produces hazardous fumes. Additionally, the need to add a glass fiber increases manufacturing complexity and cost. Furthermore, the glass fiber material itself may be difficult to recycle.
An alternative form of surface covering provides a flocked layer adhered to a substrate via an adhesive. However, as discussed above, adhesives, and any solvents associated with such adhesives, contribute to pollution in the environment surrounding the production and possibly the installation process. Additionally, the use of liquid adhesives during the production process poses difficulties in providing a uniform layer of adhesive. This lack of uniformity creates difficulties in adding a flocked layer to the backing material. Therefore, providing an attractive, preprinted flocking layer to a backing material covered in a liquid adhesive has typically been difficult.
Surface coverings in the form of floor tiles are known. Conventional floor tiles are stiff and relatively inflexible. Bending a conventional floor tile through a bend radius equal to its thickness results in substantial damage to the tile. For example, the tile may suffer creasing or cracking resulting in cosmetic or structural damage that renders the tile unfit for use.
Conventional floor tiles are further disadvantaged by cosmetic weaknesses. When used to form a floor covering conventional surface covering tiles tend to slip when in contact with one another. The edge of a first tile thus slides against the edge of a second neighboring tile during installation. The resulting slippage between tiles is later evident as a seam that is visible by the naked and untrained eye.
Heterogeneous and homogeneous sheet vinyl and vinyl tile constitute a significant percentage of the commercial resilient flooring market. Heterogeneous vinyl comprises multiple layers which allows for greater control of the look and feel of the finished product. Homogeneous vinyl comprises a single layer of material. A typical vinyl sheet flooring is produced in a gauge of 2-4 mm thick and consists of PVC formed in 6′ wide rolls or tiles. The flooring may have a urethane or other durable wear layer because the nature of PVC is that the material is soft and prone to damage.
The market for vinyl flooring has been negatively affected by perceptions that vinyl is environmentally hazardous and difficult to recycle. But commercially, vinyl is still used extensively in healthcare and education environments, principally because of its relatively low cost, ease of installation, inflammability, and maintenance. Vinyl flooring sheet goods have installation seams that can be heat welded to eliminate fluid penetration risk which is vital in clean room and healthcare environments. Vinyl flooring is typically adhered (for example, via an adhesive) directly over a concrete or wooden sub-base. In this type of installation, the resulting flooring is very hard and provides no cushioning.
It is becoming more typical for all commercial facilities, and in particular, healthcare environments to be evaluated by users and providers for comfort, noise, and safety. The risk of patient injury due to falls that can result in extended bed stay for patients is a critical issue to the healthcare community as it is the number one cause of patient injury. Falls cause over 90,000 hospital injuries per year, adding an average of 15 days to in-patient treatment and resulting in additional cost to the healthcare system of over $10 billion annually. The risk of injury due to falls demands that hospitals and healthcare providers provide additional staff to assist with patient mobility. Also, noise within patient environments is being considered as a major component to the overall quality of the environment. Ambient noise is ever present, but the residual noise generated by the impact of foot traffic or the relocation of equipment on what are typically vinyl or other hard surfaces negatively impacts the noise environment and consequently patient recovery.
Accordingly, a desire exists for a recyclable floor covering that is relatively free of solvents during its production process and which provides a uniform bonding layer between an upper layer, for example a flocking layer, and a lower layer, for example a backing material. Further, a desire exists for a recyclable floor covering that exhibits excellent flame retardation and smoke suppression qualities, and that attenuates impact noise, absorbs impact force, and is easy to install and/or maintain.